As an identification card (ID card) or a credit card, a magnetic card which record data by means of a conventional magnetic recording method has been commonly utilized. However, a magnetic card had problems of insufficient anti-tampering with data due to the ease of rewriting of the data, of insufficient protection of data due to environmental susceptibility of magnetic record and of insufficient memory capacity. Therefore, an IC card including an IC-chip has become popular in recent years.
An IC card exchanges data by reading and writing with external equipment via an electric junction provided in the surface or a loop antenna in the card. An IC card has memory capacity larger than that of a magnetic card and has been greatly improved in security. Particularly, a noncontact-type IC card provided with an IC-chip and an antenna for information exchange with external equipment in the card, is superior in security compared to a contact-type IC card provided with an electric junction on the surface, and has come to be utilized for the purpose of data secrecy and prevention of forgery or alternation being highly required such as an IC card.
There disclosed a card, as such examples, in which the first support and the second support being laminated sandwiching an adhesive, in the layer of which sealed is an IC module including an IC-chip and an antenna (for example, JP-A No. 2000-182019 (hereinafter, JP-A refers to Japanese Patent Publication Open to Public Inspection)).
Since the IC card described in JP-A 2000-182019 exhibits high security, durability thereof has become important also with respect to forgery and alternation. Particularly, various attempts have been made to assure the durability, because an IC-chip and electric parts such as an antenna for information exchange with external equipment are included in an IC card. However, still higher durability has been required in accordance with the utilization for various purposes and pervasion. In view of IC card characteristics, required is high durability against repeated bending and stress by falling or coins while always being carried in a pocket of pants. For this purpose, improvement by providing a strong reinforcement structure in an IC-chip has been proposed.
However, although a limited improvement of durability was observed, there caused a crack of an IC-chip or a break of a card to make electric operations impossible due to insufficient durability in various situations, resulting in problems of impossible confirmation of card certification information or personal certification information.
Further, in case of data in an IC-chip had been tampered or intentionally broken by a third person with malice, it was difficult to judge whether the IC card or the IC-chip was true or false, or whether it had been damaged during the manufacturing process. Conventionally, an IC card in which intrinsic information for card certification or personal certification information is provided in an IC-chip not as to be easily readable and a serial number is visually printed on the surface by such as a laser, has been utilized, however, there was not necessarily a sufficient effect to prevent forgery and alternation against a third person with malice, who might tamper the data while leaving the serial number because it was visible. Further, printing visually on the surface might limit the design of an IC card and tended to allow misuse by a third person with malice.
There is a possibility that intrinsic information may be tampered, forged or misused by a third person with malice when intrinsic information is provided on the card surface as visible information. Although security of a card is improved by providing intrinsic information on the card surface as invisible information, there is a possibility that the card may be tampered and misused by scratching the surface when the information is once made visible and recognized.
Further, also in the manufacturing process of an IC card, in case that information in an IC-chip became unreadable, there was a problem of time-consumption for the investigation to pursue the reason and reproduce the card, resulting in delay of reissue and decrease of manufacturing yield and efficiency.